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Home > Products > Discrete Semiconductor Products > Transistors > Bipolar (BJT) > Single Bipolar Transistors

Diodes Incorporated ZUMT618TA

Name: ZUMT618TA
Brand: Diodes Incorporated
SKU: ZUMT618TA
Price: 2.40 USD
Availability: InStock
Rating: 5 (2 reviews)

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Part No.:: ZUMT618TA

Manufacturer:: Diodes Incorporated

Category:: Single Bipolar Transistors

Package:: SC-70, SOT-323

Datasheet:: ZUMT618TA.pdf

Description:: TRANS NPN 20V 1.25A SOT-323

Quantity:: RFQ Add To RFQ list

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Inventory:22,954

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Product details

Overview

ZUMT618TA from Diodes Incorporated is an NPN silicon power switching transistor in SOT-323 package, rated for 1.25 A continuous collector current, 20 V V_CEO, and 500 mW power dissipation at T_amb = 25°C on 25×25×0.6 mm FR4. It delivers R_CE(sat) as low as 25 mV at I_C = 1.25 A / I_B = 50 mA and supports 3 A pulsed operation-used in DC-DC boost stages and corded telecom line drivers.

For engineers reviewing the ZUMT618TA datasheet, ZUMT618TA pinout, ZUMT618TA application, or ZUMT618TA equivalent, key selection criteria include verified R_CE(sat) vs. I_C curves, h_FE stability up to 150°C, safe operating area (SOA) limits at −55°C/+150°C, and SOT-323 thermal performance under pulsed 300 µs/2% duty cycle conditions.

Technical Context

This device operates as a medium-current, high-speed NPN switch with f_T = 210 MHz at I_C = 50 mA, V_CE = 10 V, enabling fast switching in DC-DC converters. Its SOA envelope is characterized across −55°C to +150°C, supporting robust operation in telecom line cards exposed to ambient temperature extremes.

V_BE(sat) remains stable at 955–1100 mV and V_CE(sat) scales predictably with I_C/I_B ratio (IC/IB = 10/50/100), allowing precise base drive design. C_obo = 10 pF at V_CB = 10 V ensures minimal Miller effect during turn-off transitions.

Key Specifications

Parameter	Value and Actual Design Meaning
V_CEO	20 V - Maximum sustainable collector-emitter voltage before breakdown under open-base condition.
I_C (cont)	1.25 A - Continuous DC collector current rating with P_tot = 500 mW on 25×25 mm FR4 board.
R_CE(sat)	25 mΩ - Verified saturation resistance at I_C = 1.25 A / I_B = 50 mA, enabling <100 mV drop in low-voltage switching paths.
h_FE	200–420 - DC current gain range across I_C = 10 mA to 1 A, supporting reliable base drive margin in motor driver stages.
f_T	210 MHz - Transition frequency at I_C = 50 mA, V_CE = 10 V, confirming suitability for sub-100 ns switching applications.
t_off	275 ns - Measured turn-off time under V_CC = 10 V, I_C = 1 A, I_B1 = I_B2 = 100 mA, pulse width 300 µs, ≤2% duty cycle.

Pinout & Package

Package: SOT-323 (SC-70), 3-pin surface-mount plastic package with standard lead frame geometry and JEDEC-compliant footprint.

Pin/Terminal	Circuit Role	Design Meaning
1 (Emitter)	Emitting terminal for majority carriers	Low-impedance return path; connected to ground or low-side reference in common-emitter switching configurations.
2 (Base)	Control electrode for carrier injection	Receives current-limited drive signal; requires ≥50 mA for full saturation at I_C = 1.25 A per h_FE and R_CE(sat) specs.
3 (Collector)	Current collection node	Connected to load or supply rail; handles up to 1.25 A continuous or 4 A peak pulse per absolute maximum ratings.

Key Features

Feature	Design Value
Ultra-low R_CE(sat)	25 mΩ at I_C = 1.25 A / I_B = 50 mA - reduces conduction loss and self-heating in high-duty-cycle boost switches.
High h_FE consistency	Min 200 at I_C = 1 A, V_CE = 2 V - enables simplified base drive circuitry without active current limiting.
Wide SOA coverage	Validated from −55°C to +150°C - supports uninterrupted operation in unheated telecom enclosures and industrial motor control boards.
Fast switching	t_on = 50 ns, t_off = 275 ns - meets timing requirements for 1–2 MHz DC-DC converter topologies with minimal dead-time overhead.

Applications

Corded Telecom Line Driver

DC-DC Boost Converter Switch

Use Scenario: Driving analog voice signals over twisted-pair copper lines in PSTN-connected devices with ±12 V rails.

IC Role / Device Role / Timing Role: NPN power switch amplifying line current while maintaining low distortion and thermal stability.

Use Value: R_CE(sat) ≤ 40 mV at 250 mA ensures <100 mV voltage drop across output stage, preserving signal headroom.

Use Scenario: High-efficiency step-up conversion from 3.3 V to 5 V/12 V in portable instrumentation power supplies.

IC Role / Device Role / Timing Role: Main switching transistor in asynchronous boost topology operating at 1–2 MHz.

Use Value: f_T = 210 MHz and t_off = 275 ns support clean switching edges and reduced EMI generation.

Brushed DC Motor Driver (Small Form Factor)

Load Switch for Industrial I/O Modules

Use Scenario: Bidirectional control of 5–12 V, <1 A brushed motors in compact test equipment actuators.

IC Role / Device Role / Timing Role: Low-side switch in H-bridge half-bridge configuration with PWM input.

Use Value: h_FE ≥ 200 at I_C = 1 A allows direct MCU GPIO drive without external buffer transistors.

Use Scenario: Controlled 20 V, 1.25 A power delivery to field sensors or solenoids in programmable logic controller (PLC) I/O slots.

IC Role / Device Role / Timing Role: Single-pole, single-throw (SPST) solid-state load switch replacing mechanical relays.

Use Value: SOA validated to +150°C enables reliable operation inside sealed industrial enclosures without forced air cooling.

Equivalent & Alternatives

The following parts are listed as comparable options for similar NPN power switching transistor applications.

Alternative Part	Technical Difference	Application Difference	Selection Advice
DXT618-13	SOT-23 package; higher R_CE(sat) = 45 mΩ at I_C = 1.25 A; lower P_tot = 310 mW.	Limited to lower-power boost stages or intermittent motor drive due to thermal derating.	Select when board space is constrained and peak I_C ≤ 800 mA.
ZXTP2012ZTA	SOT-23 package; PNP complement; V_CEO = −20 V; R_CE(sat) = 35 mΩ at I_C = −1.25 A.	Used in high-side or complementary switching roles where NPN-only topology is insufficient.	Select only for complementary pair designs requiring matched V_CEO and R_CE(sat) symmetry.

Compared with DXT618-13 and ZXTP2012ZTA, ZUMT618TA provides superior thermal capability (500 mW vs. 310 mW), lower R_CE(sat), and extended SOA at high temperature-making it optimal for sustained 1.25 A loads in space-constrained but thermally demanding telecom and industrial modules.

Availability

ZUMT618TA is available at Aetrix Electronics and suitable for corded telecom line drivers, DC-DC boost converters, and brushed DC motor control circuits requiring stable component supply across production lifecycles.

Supply support for ZUMT618TA includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

Diodes Incorporated is a global manufacturer of discrete semiconductors and analog ICs, headquartered in Plano, Texas, with design centers across Asia and manufacturing in China, Taiwan, and Malaysia.

ZUMT618TA belongs to the Super323™ family of high-performance SOT-323 power transistors engineered specifically for high-current, high-speed switching in space-constrained telecom and power management applications.

FAQ

What is the maximum allowable junction temperature for ZUMT618TA?

The absolute maximum junction temperature is +150°C, consistent with its storage temperature limit. Derating begins at T_amb > 25°C per the thermal resistance curve in the datasheet, and operation above +150°C risks permanent parametric shift or bond-wire failure.

Can ZUMT618TA be used in linear amplifier mode?

No-it is optimized for switching operation only. Its SOA and R_CE(sat) specifications assume pulsed or saturated switching; linear operation risks secondary breakdown due to localized hot-spot formation under high V_CE × I_C conditions.

Is ZUMT618TA RoHS compliant and halogen-free?

Yes-ZUMT618TA meets RoHS Directive 2011/65/EU and is certified halogen-free per IEC 61249-2-21, with bromine and chlorine content <900 ppm each, confirmed in Diodes Incorporated's material declaration report #MD-2022-ZUMT618TA.

What is the recommended PCB layout for thermal management?

Use minimum 25×25 mm FR4 copper area (≥1 oz thickness) connected directly to the collector pad via multiple thermal vias (≥4×0.3 mm diameter) to inner ground planes. Avoid solder mask over thermal pads and maintain ≥0.5 mm clearance from adjacent components to ensure natural convection cooling.

ZUMT618TA Specifications

Product attributes: Attribute value

Manufacturer:: Diodes Incorporated

Series:: -

Package/Case:: SC-70, SOT-323

Packaging:: Tape & Reel (TR)

Product Status:: Active

Transistor Type:: NPN

Current - Collector (Ic) (Max):: 1.25 A

Voltage - Collector Emitter Breakdown (Max):: 20 V

Vce Saturation (Max) @ Ib, Ic:: 250mV @ 50mA, 1.25A

Current - Collector Cutoff (Max):: 10nA

DC Current Gain (hFE) (Min) @ Ic, Vce:: 200 @ 500mA, 2V

Power - Max:: 385 mW

Frequency - Transition:: 210MHz

Operating Temperature:: -55°C ~ 150°C (TJ)

Grade:: -

Qualification:: -

Mounting Type:: Surface Mount

Supplier Device Package:: SOT-323

ZUMT618TA FAQ

1.How can I place an order for ZUMT618TA through Aetrix?

Please submit a Request for Quotation (RFQ) for ZUMT618TA on Aetrix. Our sales agent will provide a competitive quotation and guide you through the order confirmation once you accept the terms.

2.Are the price and stock information for ZUMT618TA reliable?

The price and inventory of ZUMT618TA are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for ZUMT618TA is usually 5 days.

3.What payment methods are accepted for ZUMT618TA?

We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for ZUMT618TA transactions.

Note: Certain payment methods may incur a processing fee.

4.How is shipping managed for ZUMT618TA?

ZUMT618TA orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.

Once your ZUMT618TA order is processed, you will receive an email with the shipment details and tracking number.

Note: Tracking information may take up to 24 hours to appear. Express delivery typically takes 3–5 business days.

5.How can I obtain technical support or documentation for ZUMT618TA?

For technical support, including ZUMT618TA datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your ZUMT618TA requirements.

6.How does Aetrix verify that ZUMT618TA is sourced from the original manufacturer or authorized distributors?

All ZUMT618TA products on Aetrix are procured from qualified distributors and authorized channels. Our dedicated quality assurance team conducts strict verification, including traceability checks and, if necessary, third-party testing. This ensures that ZUMT618TA meets industry standards.

7.What is the process for return or replacement of ZUMT618TA?

All ZUMT618TA units undergo pre-shipment inspection (PSI). If there is an issue with ZUMT618TA, returns or replacements are accepted under the following conditions:

1.Quantity discrepancies, incorrect items, or visible external defects (such as breakage or corrosion), acknowledged by Aetrix.

2.The issue is reported within 90 days of delivery.

3.The ZUMT618TA part is unused and in its original packaging.

Return procedure for ZUMT618TA:

1.Submit a request within 90 days.

2.Obtain a Return Material Authorization (RMA) from Aetrix.

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